Electromagnetic analysis of YBCO superconducting cables with high current transporting for electric devices

Most high-temperature superconducting (HTS) electric devices have been built by employing a superconducting composite cable. These HTS devices generally have large current-carrying capacities. Therefore, the electromagnetic characteristic of a composite superconducting cable with high current density becomes a key point for the application of these HTS devices. A helical superconducting cable and a Roebel cable consisted of YBCO-coated conductors with a critical current of 500 A @ 77 K in the self-field are both proposed in this paper. The helical superconducting cable that has two conductor layers and the structure parameters of the helical cable are given. The Roebel cable has four layers with a critical current of 500 A. Two 3-D models are built for a helical cable and a Roebel cable with variable geometries. Their magnetic flux distributions along the axis are presented based on the finite-element analysis method, and their electromagnetic characteristics are discussed as well. The analysis model can be further applied for the large-scale HTS electric device design with high current-carrying ability.